CVE-2026-33167

Severity CVSS v4.0:
LOW
Type:
CWE-79 Cross-Site Scripting (XSS)
Publication date:
23/03/2026
Last modified:
24/03/2026

Description

Action Pack is a Rubygem for building web applications on the Rails framework. In versions on the 8.1 branch prior to 8.1.2.1, the debug exceptions page does not properly escape exception messages. A carefully crafted exception message could inject arbitrary HTML and JavaScript into the page, leading to XSS. This affects applications with detailed exception pages enabled (`config.consider_all_requests_local = true`), which is the default in development. Version 8.1.2.1 contains a patch.